linux/arch/x86/include/asm/stat.h
Linus Torvalds 8529f613b6 vfs: don't force a big memset of stat data just to clear padding fields
Admittedly this is something that the compiler should be able to just do
for us, but gcc just isn't that smart.  And trying to use a structure
initializer (which would get us the right semantics) ends up resulting
in gcc allocating stack space for _two_ 'struct stat', and then copying
one into the other.

So do it by hand - just have a per-architecture macro that initializes
the padding fields.  And if the architecture doesn't provide one, fall
back to the old behavior of just doing the whole memset() first.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-06 18:02:40 -07:00

136 lines
2.9 KiB
C

#ifndef _ASM_X86_STAT_H
#define _ASM_X86_STAT_H
#define STAT_HAVE_NSEC 1
#ifdef __i386__
struct stat {
unsigned long st_dev;
unsigned long st_ino;
unsigned short st_mode;
unsigned short st_nlink;
unsigned short st_uid;
unsigned short st_gid;
unsigned long st_rdev;
unsigned long st_size;
unsigned long st_blksize;
unsigned long st_blocks;
unsigned long st_atime;
unsigned long st_atime_nsec;
unsigned long st_mtime;
unsigned long st_mtime_nsec;
unsigned long st_ctime;
unsigned long st_ctime_nsec;
unsigned long __unused4;
unsigned long __unused5;
};
/* We don't need to memset the whole thing just to initialize the padding */
#define INIT_STRUCT_STAT_PADDING(st) do { \
st.__unused4 = 0; \
st.__unused5 = 0; \
} while (0)
#define STAT64_HAS_BROKEN_ST_INO 1
/* This matches struct stat64 in glibc2.1, hence the absolutely
* insane amounts of padding around dev_t's.
*/
struct stat64 {
unsigned long long st_dev;
unsigned char __pad0[4];
unsigned long __st_ino;
unsigned int st_mode;
unsigned int st_nlink;
unsigned long st_uid;
unsigned long st_gid;
unsigned long long st_rdev;
unsigned char __pad3[4];
long long st_size;
unsigned long st_blksize;
/* Number 512-byte blocks allocated. */
unsigned long long st_blocks;
unsigned long st_atime;
unsigned long st_atime_nsec;
unsigned long st_mtime;
unsigned int st_mtime_nsec;
unsigned long st_ctime;
unsigned long st_ctime_nsec;
unsigned long long st_ino;
};
/* We don't need to memset the whole thing just to initialize the padding */
#define INIT_STRUCT_STAT64_PADDING(st) do { \
memset(&st.__pad0, 0, sizeof(st.__pad0)); \
memset(&st.__pad3, 0, sizeof(st.__pad3)); \
} while (0)
#else /* __i386__ */
struct stat {
unsigned long st_dev;
unsigned long st_ino;
unsigned long st_nlink;
unsigned int st_mode;
unsigned int st_uid;
unsigned int st_gid;
unsigned int __pad0;
unsigned long st_rdev;
long st_size;
long st_blksize;
long st_blocks; /* Number 512-byte blocks allocated. */
unsigned long st_atime;
unsigned long st_atime_nsec;
unsigned long st_mtime;
unsigned long st_mtime_nsec;
unsigned long st_ctime;
unsigned long st_ctime_nsec;
long __unused[3];
};
/* We don't need to memset the whole thing just to initialize the padding */
#define INIT_STRUCT_STAT_PADDING(st) do { \
st.__pad0 = 0; \
st.__unused[0] = 0; \
st.__unused[1] = 0; \
st.__unused[2] = 0; \
} while (0)
#endif
/* for 32bit emulation and 32 bit kernels */
struct __old_kernel_stat {
unsigned short st_dev;
unsigned short st_ino;
unsigned short st_mode;
unsigned short st_nlink;
unsigned short st_uid;
unsigned short st_gid;
unsigned short st_rdev;
#ifdef __i386__
unsigned long st_size;
unsigned long st_atime;
unsigned long st_mtime;
unsigned long st_ctime;
#else
unsigned int st_size;
unsigned int st_atime;
unsigned int st_mtime;
unsigned int st_ctime;
#endif
};
#endif /* _ASM_X86_STAT_H */